1 82 PROBLEMS OF GENETICS 



There can scarcely be a doubt that the distinction between 

 aurita and ramosa is factorial, the radiate ramosa probably having 

 the factor for striping. In support of this view may be men- 

 tioned the observation of Boisduval, 24 respecting a gynandro- 

 morphous individual, which was aurita male on one side, and 

 ramosa female on the other. Speyer makes another excellent 

 comment. He points out that the simple notion that the radi- 

 ation is a mere extension of pigmentation consequent on the 

 climate of the higher levels, will not fit the facts very easily, 

 because the size of the spots varies greatly in aurita itself at any 

 level, and lowland specimens may actually have more black 

 confined to the spots alone than some ramosa possess on spots and 

 lines combined. 25 



The two Salamanders, S. maculosa and its Alpine form atra, 

 might not improbably furnish evidence bearing on the same 

 problem. The two are of course very distinct, not merely in 

 colour (maculosa being spotted with yellow or orange while atra 

 is entirely black) but also in the mode of reproduction, a feature 

 to which reference will be made in the next chapter. I cannot, 

 however, find any evidence as to the overlapping of the two forms. 

 S. atra occurs from about 3,000 feet or somewhat less, and reaches 

 great elevations in the Eastern Alps, but I do not know if the 

 two forms ever occur in the same localities. Leydig, 26 Boulenger, 27 

 and most modern authorities regard the two types as distinct 

 species, but they are in any case closely allied, and it would be of 

 interest to have exact knowledge of their geographical delimi- 

 tations. 



The reader who has considered the cases adduced will ap- 

 preciate the difficulties which must be faced in any attempt to 



normal lubricipeda in also found on the island. For references as to the British 

 occurrences see especially, Hewett, W., Naturalist, 1894, p. 353. As to Zatima see 

 especially Krancher, Soc. Ent., II, 1887-8, p. 26. I am indebted to Dr. Hartlaub 

 for information as to the Heligoland types. 



24 Boisduval, Bull. Soc. Ent. Fr., Ill, 1834, p. 5. 



25 The systematics of Setina have been much controverted, but no one I believe 

 doubts that aurita and ramosa are forms of one species. See also Chapman, A. T., 

 Ent. Rec., XIII, 1901, p. 139. 



Arch. Naturg., 33, 1867, p. 116. 



27 Brit. Mus. Cat., Batrachia Gradientia, 1882. 



